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Resistencia extrema al deslizamiento en una aleación nanocristalina estructuralmente estable
K A Darling1, M Rajagopalan2, M Komarasamy3
1Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005, USA.
Nature
|September 16, 2016
Resumen
Las nuevas aleaciones nanocristalinas de cobre y tántalo ofrecen una resistencia superior a la corrosión. Este avance supera las limitaciones de los metales nanocristalinos tradicionales, permitiendo aplicaciones a altas temperaturas.
Área de la Ciencia:
- Ciencias de los materiales
- Trabajos de metalurgia
- Nanotecnología
Sus antecedentes:
- Los metales nanocristalinos exhiben una mayor resistencia a temperatura ambiente debido al tamaño reducido del grano.
- Sin embargo, esta resistencia a menudo se obtiene a costa de una escasa resistencia al deslizamiento, lo que limita su uso en aplicaciones de alta temperatura.
- El aumento del volumen del límite de grano en los materiales nanocristalinos facilita los mecanismos de arrastre como el deslizamiento y la rotación.
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